BrowserSeal

BrowserSeal is the fastest multi browser website screenshot tool available today. It allows you to capture an image of your web site under multiple browsers with a single click of a mouse and instantly inspect the differences. It runs on all versions of Windows and supports Internet Explorer (IE6, IE7 and IE8), Firefox (3.0 and 3.5), Google Chrome, Opera (8, 9 and 10) and Safari (3 and 4).
It is not just a screenshot application, it comes with standalone versions of all major browsers, allowing the developer not only to verify the web site layout under all browsers, but also troubleshot the issue in case of a problem.